This disclosure relates generally to equipment utilized and operations performed in drilling of subterranean wells and, in an example described below, more particularly provides floating plug pressure equalization in drill bits of the type used to drill wellbores in the earth.
Lubricant is used in drill bits for various purposes, among which is to exclude well fluids and debris from interfaces between components of the drill bits that move relative to one another. For example, lubricant can be used between cones of a tri-cone bit and journals on which the cones rotate.
Preferably, the lubricant is maintained at a pressure which is substantially equal to that in its environment, so that seals which isolate the lubricant from well fluids in the environment do not have to withstand significant pressure differentials in use. Therefore, it will be appreciated that improvements are continually needed in the art of pressure equalization for drill bits.